Background Physical rehabilitation exercise (PRE) is commonly prescribed in the early stage after total hip arthroplasty (THA). However, systematic reviews investigating the effectiveness of PRE have reported diverse results, and often included trials using PRE in both groups or initiated at a later stage after surgery, which does not reflect clinical practice. Therefore, the study objective was to investigate whether early initiated PRE following THA was superior to no PRE in terms of improving function, reducing pain and increasing quality of life at end of intervention and 12 months after surgery. Methods A systematic review of randomized controlled trials (RCT) was conducted. Included studies were RCTs comparing PRE initiated within 3 months after primary THA due to osteoarthritis with no PRE. MEDLINE, Embase, Cinahl, Cochrane and Pedro were searched for published articles, while Scopus, Web of Science, Clinical Trials.gov and WHO International Clinical Trials Registry Platform were searched for conference papers and pre-registered trials. Study methodology was assessed by Cochrane Risk of Bias 2 (RoB2) tool and overall quality of evidence by the Grading of Recommendations Assessment, Development and Evaluation approach (GRADE). Incomplete outcome data and heterogeneity among studies precluded meta-analysis. Thus, data synthesis using vote counting was applied and tested by the binomial probability test. The results were narratively presented in text and tabular form distributed on pain, patient-reported function and performance-based function. Results A total of 10742 references were screened. Three trials (two published papers and one conference abstract) with a total of 151 participants were included in the narrative synthesis. Only outcomes at end of treatment (ranging from 3-18 weeks after surgery) were available. The observed direction of effect favored PRE in the single study reporting patient-reported function, in both studies reporting pain and in two out of three studies reporting performance-based function. However, the testing did not show significant evidence of effect of PRE. Overall, a high risk of bias was present, and quality of evidence was very low. Discussion Limited and very low quality of evidence showed no clear benefits or harms of PRE. Hence, no conclusions on superiority of PRE to no PRE can be drawn. High quality randomized controlled trials are needed to determine the effectiveness of using PRE early after THA. Other Registration: PROSPERO, CRD42020203574

The authors have declared no competing interest.

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=203574

Funding was received from: The Association of Danish Physiotherapists' Fund; Graduate School of Health, Aarhus University; Department of Clinical Medicine, Aarhus University; The Danish Rheumatism Association; The Regional Hospital Central Jutland's Research Fund and The Frimodt-Heineke Fund.

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